Insol {palinsol}

Computes incoming solar radiation (insolation)

Description

Computes incoming solar radiation (insolation) for a given astronomical configuration, true solar longitude and latitude

Usage

Insol(orbit, long = pi/2, lat = 65 * pi/180, S0 = 1365, H = NULL)

Arguments

orbit

Output from a solution, such as ber78, ber90 or la04

long

true solar longitude

lat

latitude

S0

Total solar irradiance

H

Sun hour angle, in radians

Details

True solar longitude is measured in radians:

pi/2	for June solstice
pi	for September equinox
3 * pi/2	for December solstice
0	for Spring equinox

It may be obtained for a given day in the year using the function day2l.

Value

Daily-mean insolation (assuming fixed astronomical parameters during a true solar day) if 'H' is null. Otherwise, insolation at specified hour angle (H = 0 at noon, H = pi at midnight).

Author(s)

Michel Crucifix, U. catholique de Louvain, Belgium.

References

Berger, A. L. (1978). Long-term variations of daily insolation and Quaternary climatic changes, J. Atmos. Sci., 35, 2362-2367.

Examples

## make a little wrapper, with all default values

insolation <- function(times, astrosol=ber78,...)
  sapply(times, function(tt) Insol(orbit=astrosol(tt)))

tts <- seq(from = -400e3, to = 0, by = 1e3)
isl <- insolation(tts, ber78)
plot(tts, isl, typ='l')